1. Field of the Invention
The present invention relates to an inkjet recording head, a method for producing the inkjet recording head, and a semiconductor device.
2. Description of the Related Art
In the field of inkjet recording heads (hereinafter, also referred to as “recording heads”), structures having supply ports passing through substrates have been developed for various purposes. Japanese Patent Laid-Open No. 9-11478 discloses that a protective layer is formed on the wall of a supply port in order to prevent elution of a substrate material into ink.
However, ink may gradually permeate in the interface between the protective layer and a functional layer exposed at the wall of the supply port. In the case where the permeated ink reaches the substrate and where ink circulates readily through a permeation route, the amount of elution of the substrate material into ink may be increased, causing defects such as clogging of a discharge port.